1997 Vol. 21, No. 9

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Factorial Moments Continuous Order and Multifractal Analysisin 400GeV/c pp Collisions
Wang Shaoshun, Zhang Jie, Ye Yunxiu, Xiao Chenguo
1997, 21(9): 769-776.
The method of the factorial moments Fq of continuous order suggested by Hwahas been tested.It is found that this method can not be used to analyse the real experimental data. Some improvement has been made in the method, which. can be used for the real experimental data. The analytic results for the experimental pseudorapidity distributions of charged particles produced in 400GeV/ c pp collisions indecated that the method of the factorial moments of continuous order is available. And there is seemingly multifractal behavior in the process of multiplicity production in pp collisions at 400GeV/c.
Fission Angular Distributions for the Incomplete Fusion Reactions
Liu Guoxin, Chen Keliang, Yu Xian, DaiGuangxi
1997, 21(9): 777-782.
The fragment angular distributios for 16O+159Tb, 16O+197Au and 16O+209Bi reactions have been measured by the solid state track detctors. After subtraction of the contribution of intermediate mass fragment (IMF), the fission angular distributions have been fitted by the transitional state statistical model (TSM) and the single spin standard theory to extract the spins of the fission nuclei. The relation between spinsand bombarding energies is discussed.
Decay Scheme of 229Ra
Shen Shuifa, Yuan Shuanggui, Yang Weifan, Fang Keming, Mou Wantong, Zhang Zueqian, Li Zongwei, Zhong Jiquan, Guo Tianrui, Chen Zhantu
1997, 21(9): 783-786.
The 229Ra has been produced in the 232Th(n,a)229Ra reaction by 14MeV neutron irradiation of natural Thorium. The 229Ra activities were separated from irradiated target material by radiochemical separation technique. 18 new γ rays with energies 14.5,15.6,18.8,21.8,22.5,44.0,47.5,55.0,63.0,69.6,93.6,94.1,98.5,102.2,104.5,106.1,161.171.5keV attributed to the 229Ac were observed for the first time by usin γ(X) spectroscopic methods. A partial decay scheme of 229Ra was proposed.
Study of Light Propagation Characteristics of Scintillating Fibres
Wang Xiaolian, Xu Zizong, Hou Yunzhen, Wang Zhaomin, Chen Hongfang, Li Cheng, Zeng Hui
1997, 21(9): 787-792.
The light yield, time characteristics of light propagation and attenuation length of some kinds of scintillating fibres are presented in this paper. Comparison of these characteristics of several fibres is also performed.
Quantum Statistic Properties of Eigenstates of the Annihilation Operatoraqsk of Two Parameter Deformed Harmonic Oscillator
Wang Jisuo, Sun Changyong, Teng Aiping
1997, 21(9): 793-800.
In this paper, the quantum statistic properties of the eigenstates of the higher power aqsk(k≥3) of the annihilation operator of two-parameter deformed harmonic oscillator are investigated. The results show that the k states have Nth-power squeezing [N=(m+1/2)k,m=0,1,2,…] when k is even,and all of them show the antibunching effect
Monte-Carlo Simulation on Asymmetric Lattices for SU(2) Gauge Field Thermodynamics
Hu Jingguo
1997, 21(9): 801-805.
We simulate thermodynamics of SU(2) gauge field on the asymmetric lattices(ξ= 2,3). It shows that Monte-Carlo simulation on the asymmetric lattices is an effective approach of realizing continuous physics limit.
A Simple Model Describing EMC Effect,Nuclear Drell-Yan Process and Inelastic J/ψ Production
Zhu Yabo, Li Guanglie
1997, 21(9): 806-811.
A recombination factor is employed which can describe the nuclear shadowing and antishadowing effects in the small x region. Based on the consideration of the nuclear momentum conservation, a unified description of the EMC effect, nuclear Drell-Yan process and inelastic J/ψ production is given in terms of the x-rescaling model with recombination factor.
Nuclear Structure in Lead Region (Ⅱ) Non-unique First Forbidden Beta Decay for Nuclei 208Tl,208Pb and 206—208Hg
Zhang Changhua, Gu Jinnan
1997, 21(9): 812-817.
The non-unique first forbidden beta decay rates for nuclei 208Tl、208Pb and 206—208Hg are calculated using different effective interactions and model space in term of shell model. The calculated logfot are very sensitively dependent on the effective interaction.The beta decay pattems for 206Hg and 208Hg are also compared.
Chaotic Motion of Classical Particles in Axially Symmetric Potentials with Octupole Deformation
Li Junqing
1997, 21(9): 818-824.
The fact that. there are. more prolate-deformed nuclei than oblate-deformed ones in the nature is found to be related with the chaotic motion of nucleons. The primary. investigation with classical theory shows that the particle motion in the potential with oblate-plus -octupole deformation could become chaotic in the case of smaller deformation strength as compared with the case of prolate-plus-octupole deformation. The reason is that the negative curvature in the potential surface could appear in the case of smaller deformation strength for the former one rather than for the latter.
Energy Coherence and Charge Diffusion in Dissipative Reactions
Lu Jun, Wang Qi, Zhu Yongtai, Xu Hushan, Li Songlin, Zhang Yuhu
1997, 21(9): 825-830.
In the framework of transport theory, the variation of coherence energy width Γ with neutron-charge ratio N/Z for the 19F+51V dissipative reaction is compre-hensively discussed. It can be concluded that the charge equilibrium is reached in the present colliding system. The charge diffusion coefficent is also extracted from the analysis The proportional relation between Γ distribution width and average interaction time is ascribed to the charge diffusion process. The effects of cross correlation between different isotopes on fluctuation amplitude are also discussed.
Relativistic Mean-Field Calculation for Hypernuclei
Shen Yaosong, Ren Zhongzhou
1997, 21(9): 831-837.
The ground state properties of hypernuclei are studied theoretically using the relativistic mean-field theory with TM1 and NL-SH force parameters. It is found that these new parameters can very satisfactorily reproduce the ground state properties of the above hypernuclei. The parameter sets TM1 and NL-SH give a very similar description on the hypernuclei. The properties of hypernuclei in baryon hyperon systems are insensitive to the force parameters of effective nucleon-nucleon interaction. The influence of the pairing force is taken into account in the study of hypemuclei and it is found that it leads to the even-odd effect.
Study of Odd-A Tm Isotopic Chain Properties of Decoupling parameter of [411 1/2] Band
Dong Baoguo, Shen Caiwan, Chen Yoagshou
1997, 21(9): 838-843.
The deformations of the ground and low-lying excited states of the odd-A 157—173Tm isotopic chain are calculated using the Macro-Micro Cranking Model with quasiparticle configuration. Then the decoupling parameters (DPs) of 157—173Tm of [411 1/2] odd proton band. calculated and compared with the experimental results. It is emphasized that the effect of DPs of the odd-A Tm isotopic chain is caused by the γ deformation. It is pointed out that the anomalous DP of 157Tm might be caused by the band-interacting The sensitivity of the DPs to the Nilsson parameter and deformation parameters is also discussed.
Study on Lithium Fluoride Cluster-Based Nanophase Films by Low Energy Positron Beam
Ju Xin, Peng Liangqiang, Deng Bin, Weng Huimin, Han Rongdian
1997, 21(9): 844-850.
Lithium fluoride(LiF) cluster-based films deposited on monocrystalline silicon with vaporzation/ condensation method have been studied by low energy positron beam and the S parameters and the effective lengths of diffusion (Leff) in position annihilation were measured. The influences on the microstructure of LiF cluster-based films by the conditions of preparation, such as the temperature of tho substrate, the rate of tho vaporization and the partial pressure of Ar are discussed.
Research for Beam Spreading of Proton Therapy Facility
Yu Jianguo, Yu Qingchang
1997, 21(9): 851-859.
In this paper, the dual-ring double scatterng method of proton beam spreading, such as the relation of beam distribution function with beam uniformity and beam efficiency, the effection of beam misalignment the variation of beam along longitudinal direction are studied. The depths of dual -ring double scatterers corresponding to different beam field are calculated. Liquor scatterer instead of solid one is proposed.
Spin-Dependent Relativistic Effect on Heavy Quarkonium Properties in Medium
Dong Yubing
1997, 21(9): 860-864.
Spin-dependent relativistic effect on the binding and dissociation of the heavy quarkonium in a thermal environment is investigated . The result shows that the interactions could influence the heavy quarkonium properdes in medium.